Other regularly occurring British butterflies (more information based on personal experience will be added over time)
Lulworth Skipper Thymelicus acteon The only way to see this species is to make a visit to sites in Dorset ( e.g. Lulworth Cove and/or Durlston Head). The Isle of Purbeck is of course an excellent area for wildlife.
If you are looking for reptiles, it is worth joining one of the organised walks at Arne which aim to show visitors Smooth Snake and other specialities.
Silver-spotted Skipper Hesperia comma The easiest place to see Silver-spotted Skipper from the East Midlands is Aston Rowant, Oxfordshire, where the population is increasing and spreading. It can also be seen in small numbers at Denbies Hillside, Surrey.
Swallowtail Papilio machaon Although I have heard at least one report of a released specimen in Rutland, there aren’t any Rutland records which relate to natural occurrence by Swallowtail. There are several accessible sites in the Norfolk Broads, of which one of my favourites is How Hill.
Brown Hairstreak Thecla betulae This is a tricky species to photograph, though people have achieved good results recently at Shipton Bellinger, Hampshire. For those based in the East Midlands an accessible and reliable site is Whitecross Green Wood, Oxfordshire. Binoculars are useful when scanning the crowns of ash and oak.
Small Blue Cupido minimus As good a place as any to see Small Blue from the East Midlands is Totternhoe Knolls, Bedfordshire, where in late May it is also possible to see Duke of Burgundy.
Northern Brown Argus Plebeius artaxerxes Good places to see this species in northeast England include Bishop Middleham in Co. Durham which is also good for orchids; in the northwest it can be found at Arnside Knott, Cumbria and Gait Barrows, Lancashire, both of which are excellent sites for a variety of butterflies and plants.
Adonis Blue Polyommatus bellargus Despite its expansion of range since the 1990s this species still has a southern distribution. A reliable site within easy reach of the East Midlands is Denbies Hillside, Surrey, where there were also 1000s of Chalkhill Blues as well as Silver-spotted Skipper in August 2012. An alternative is Rodborough Common, Gloucestershire, which also has Duke of Burgundy.
Large Blue Glaucopsyche arion The Large Blue once occurred as close to Rutland as Northamptonshire, where in 1860 a single dealer took 200 adults. The story of its subsequent national extinction by 1979 and reintroduction is well documented. A good place to see this species currently is Collard Hill in Somerset, which is also an excellent site for orchids.
Marsh Fritillary Euphydryas aurinia
Glanville Fritillary Melitaea cinxia Although the main British stronghold of this species is on the Isle of Wight, it can also be seen on the mainland at Hurst Castle, Hampshire (which is just as well since on the day I visited IOW it was pouring with rain!). Hurst Castle can be reached by walking along the shingle spit or, more easily, by taking the regular small ferry from Keyhaven. The Glanville Fritillaries are in the meadow north of the castle.
Heath Fritillary Melitaea athalia The most accessible site for this localised species from the East Midlands is probably Blean Woods in Kent. This one was photographed in the 1980s at the Luckett Reserve in Cornwall.
Mountain Ringlet Erebia epiphron The easiest place to find Mountain Ringlet from the East Midlands is Irton Fell, Cumbria, which can easily be combined with a visit to Meathop Moss and/or nearby limestone outcrops like Latterbarrow.
Scotch Argus Erebia aethiops Douglas listed this species for Rutland, but his doubts about the record are clearly justified and it should be regarded as erroneous. From the East Midlands the most easily accessible site is Arnside Knott, Cumbria, where it can be seen easily. Arnside is very scenic, and has an impressive variety of other butterflies and flowering plants including orchids.
Large Heath Coenonympha tullia The two most reliable sites close to the east Midlands are Meathop Moss, Cumbria, which can be combined with Mountain Ringlet (above) or Whixall Moss, Shropshire, which can be combined with Silver-studded Blue.